It’s A Start

I set off early to meet Andy at Oakenclough where we planned maintenance of net rides and bamboo poles in preparation for our autumn and winter ringing on site. We leave the 12ft poles there in all weathers so as to minimise lugging them around each time we visit. Insulation tape stops water seeping into the bamboo and also helps the net loops slide up and down. 

Bamboos

Although all seemed quiet we decided to put a couple of nets up as we repaired the poles one-by-one. To be truthful we didn’t expect much of a catch so were pleasantly surprised with the outcome. 

After four hours we called it a day with a catch of 29 birds of 11 species. This included one Willow Warbler recapture from April 2017, a resident male. Our totals: 8 Willow Warbler, 6 Goldcrest, 3 Chiffchaff, 3 Robin, 2 Great Tit, 2 Blue Tit, 1 Goldfinch, 1 Chaffinch, 1 Sedge Warbler, 1 Tree Pipit and 1 Redstart. 

Ageing autumn Willow Warblers in the field is well-nigh impossible but much easier in the hand. The potential problem is that adults go through a complete autumn moult while juveniles undertake a partial moult, so that by late summer/early August individual birds of different ages appear the same. In the hand, in general but not absolutely, adults have whiter bellies than first year birds but this on its own and because of the separate moult strategies and species’ races variation, is not enough to separate the two age groups. Reliable ageing of this species also involves checking the wear and shape of both tail feathers and flight feathers and then comparing the ground colour and the gloss of the same feather tracts. 

Willow Warbler - adult

Willow Warbler- juvenile/first year

Oakenclough is a strictly woodland site where we expect to catch woodland species. Imagine our surprise then to catch a Sedge Warbler, the first ever here. When we thought about it more, the emergent vegetation that lines the margins of a nearby reservoir fits the bill of a Sedge Warbler’s preferred reed scrub habitat, but we don’t expect to catch another.

Sedge Warbler

The Sedge Warbler had classic fault bars across the tail. Fault bars are translucent cross stripes where during the growth of the feather a disturbance has taken place, under stressful and adverse environmental conditions, usually hunger and/or bad weather,

Fault Bars - Sedge Warbler

We don’t catch many Redstarts, here or anywhere so were pleasantly surprised to find we had a juvenile/first year male. 

Redstart

Redstart

Our catch of Goldcrest included three juveniles/first year birds from on-site or very close-by. 

Goldcrest

We caught a single Tree Pipit, a species which bred here until about the early 1980s when habitat changes and range retraction led to quite marked losses in breeding numbers. 

Tree Pipit

 

The graph below shows the population changes of Tree Pipit found by combined results from Common Bird Census and Breeding Bird Survey 1966 -2009, BTO. 

Tree Pipit - BTO

Species noted but not caught today included Swallow, Pied Wagtail, Great-spotted Woodpecker, Lesser Redpoll and Kestrel.

Well, what do you know? two o' clock and it's raining again. At  least we made a start on our Oakenclough year.

Linking today to Eileen's Saturday and Stewart's World Bird Wednesday.